Ergonomic microbial air sampler

ABSTRACT

A gas sampler device has a top plate with a concaved outer wall. The concaved outer wall allows users easily to lift the top plate off of the bottom plate without disturbing the bottom plate because the curved surface permits more positive contact between the outer wall and users&#39; fingers. Moreover, the weight of the top plate is reduced by approximately twenty percent compared to conventional top plates, a feature that also makes it easier for users to lift the top plate off of the bottom plate.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a microbiological gas sampler. Moreparticularly, the present invention is for a microbiological gas samplerfor use in a controlled environment that includes an ergonomic top platewith concaved sidewalls. The concaved sidewalls allow both more positivecontact when attempting to grasp the top plate and a reduction of theweight of the device.

Background of the Related Art

A controlled environment is an area which is designed, maintained, orcontrolled to prevent particle and microbiological contamination ofproducts. Controlled environments include, for example, clean rooms andclean hoods. There are different levels of cleanliness in clean rooms,generally in the range of a Class 100 room (i.e., a room having no morethan 100 particles of 0.5 micron and larger, per cubic foot of air), toa Class 10,000 clean room.

Clean rooms are used for a variety of purposes, such as in themanufacture of pharmaceutical products and electronics, such assemiconductors. Often, clean rooms are used to work on extremelyexpensive and complex products, and it is not unusual that there bemillions of dollars worth of product in a clean room at any given time.Clean rooms have to maintain a high level of cleanliness, or risk largefinancial losses. If a product being developed or manufactured in aclean room becomes contaminated, the entire product in the clean roommust often be discarded.

Microbial air samplers are used to monitor the level of cleanliness (interms of viable contamination) in a controlled environment. One or moresamplers are positioned about the clean room to collect airborneparticulates and organisms (or microorganisms) such as bacteria andfungi. Samplers that run at high flow rates permit air to enter thesampler at such high flow rates that loss of smaller particulatescarrying microorganisms is normality (i.e., smaller particulates are notretained in the medium). At the same time high flow rate air samplersonly sample for a short time period and relay on a short snapshot of thecondition of the area. Samplers running at 28.3 LPM (liters per minute)must operate for a longer period of time than a unit running at 322 LPM.In doing this, they sample a broader spectrum of the drug fill time andpresent superior data as the sample time takes a larger snapshot of theoperation. Samplers that run at 28.3 LPM also provide the ability tocapture more smaller particulates that may be lost due to dynamic drag(or an umbrella affect) in higher flow rate units.

Air sampling systems are generally known, and an air sampling system isoffered by Veltek Associates, Inc. known as SMA (SterilizableMicrobiological Atrium) Microbial Air Sampler System. One such system isshown in U.S. Pub. No. 2011/0167931, filed Jan. 12, 2010, and U.S. Pat.No. 7,940,188, filed Jul. 26, 2010, the entire contents of which arehereby incorporated by reference. As noted in those applications, theair sampler system includes a controller connected to a vacuum pump tocontrol the flow of air to air sampler devices located in the cleanroom.

A prior art air sampler device 5 is shown in FIGS. 1(a), (b), which isoffered by Veltek Associates, Inc. The assembled air sampler device 5includes a top plate 10 with holes 11 and a bottom plate 14. The topplate 10 has a flat section and an outer side. The flat section formsthe top surface of the top plate 10 and extends substantiallyhorizontally when in use. The openings pass through the flat section.The outer side extends downward to be substantially orthogonal to theflat section. The outer side has a single uniform thickness that extendsthe entire circumference of the top plate 10. The outer surfaces of thetop plate 10 and the bottom plate 14 are flat and smooth. The bottomplate 14 is sized and shaped substantially the same as the top plate 10.Though the device 5 is shown as circular, other shapes may be used.

In operation, the top plate 10 is removed, a Petri dish is placed on thebottom plate 14, and the top plate 10 is replaced on the bottom plate14. A vacuum tube is attached to the air port 22. Air is then sucked inthrough the holes 11 in the top plate 10, so that the air strikes a testmedium contained in a Petri dish, which is inside the air sampler device5 between the top plate 10 and the bottom plate 14. The air exitsthrough the air port 22 and vacuum tube. At the end of the testingperiod, the top plate 10 is again taken off of the bottom plate 14, thePetri dish is removed, and the top plate 10 is replaced. The Petri dishcan then be analyzed to determine the level of cleanliness of the cleanroom.

The entire device 5 is metal so that the device 5 can be sterilized byheat, steam, Vaporized Hydrogen Peroxide (VHP) or Ethylene Oxide (ETO).The Petri dish has a diameter of about 3.5 inches. The top plate 10 hasan outer diameter of 4.5 inches. There are twelve holes 11 positionedwithin about a circular area having a 3 inch diameter, and each hole 11has a diameter of about 0.5 inches.

However, the sides of the top plate 10 are smooth and the top plate 10is relatively heavy, specifically, 1 pound, 4.2 ounces. Consequently,the top plate 10 can be difficult to grasp by a person inside the cleanroom who is wearing gloves.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the invention to provide a device forsampling viable cells in air. It is another object of the invention toprovide a microbial air sampler having an improved design that bothdecreases the weight of the top plate and allows for more positivecontact when grasping the top plate.

Accordingly, an air sampler device is provided having a concavedsidewall along the outer circumference of the top plate. The concavedsidewall is particularly useful because users are often required to weargloves at all times while inside the clean room. The concaved sidewallallows the top plate to be easily lifted off of the bottom plate withoutdisturbing the bottom plate because more positive contact can be madebetween the fingers of the user and the sidewall of the top plate.

Moreover, the concaved sidewall decreases the weight of the device byapproximately twenty percent. The decreased weight of the top plate alsomakes it easier for users to lift the top plate off of the bottom plate.

These and other objects of the invention, as well as many of theintended advantages thereof, will become more readily apparent whenreference is made to the following description, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1(a) is a perspective view of the air sampler device in accordancewith the prior art;

FIG. 1(b) is a cross section view of the air sampler device inaccordance with the prior art;

FIG. 2 is a top perspective view of the top plate of the air samplerdevice in accordance with an exemplary embodiment of the invention; and

FIG. 3 is a cross-section side view of the air sampler device of FIG. 2showing movement of air within the device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In describing a preferred embodiment of the invention illustrated in thedrawings, specific terminology will be resorted to for the sake ofclarity. However, the invention is not intended to be limited to thespecific terms so selected, and it is to be understood that eachspecific term includes all technical equivalents that operate in similarmanner to accomplish a similar purpose. Preferred embodiments of theinvention are described for illustrative purposes, it being understoodthat the invention may be embodied in other forms not specifically shownin the drawings.

As shown in FIG. 2 , a top plate 100 of an air sampler device 50 isshown. The top plate 100 has a top surface 112. There are twelve holes116 formed in the top surface 112. The top plate 100 has a flat section130 and at least one outer side 140. The flat section 130 forms the topsurface of the top plate 100 and extends substantially horizontally whenin use. The openings 116 pass through the flat section 130. The outerside or side wall 140 extends downward to be substantially orthogonal tothe flat section 130. The side wall 140 is concaved or curved inward anddefines the entire outer circumference of the top plate 100. Theconcaved outer side 140 makes the top plate 100 easy to grip, so that auser can easily remove and replace the top plate 100 with respect to thebottom plate 150.

For illustrative purposes, the bottom plate 150 is also shown in FIG. 3. A vacuum air port 160 is positioned at the side of the bottom plateand communicates with an air hole 162. The air hole 162 extends throughthe bottom plate 150, from the air port 160 to the center well 158. Thevacuum air port 160 connects to a vacuum tube to draw air through thesampler 50.

The operation of the sampler 50 is best shown in FIG. 3 , where thearrows generally show the direction of travel of the air as it flowsthrough the device 50. A sterilized air sampler device 50 is introducedinto the clean room, and the top plate 100 is removed. The Petri dish 52is inserted onto the bottom plate 150, and the top plate 100 isreplaced. The air flow is then initiated for a predetermined period oftime. Air is drawn into the sampler device 50 by the vacuum tube 162through the air port 160.

Once the air enters the holes 112 in the top plate, it strikes thecapture material in the Petri dish 52, then travels up around the sidesof the Petri dish 52, through the elongated slots 164 beneath the Petridish 52, and enters the center well 158. The air is then sucked throughthe air hole 162 and exits out of the vacuum air port 160. Once thepredetermined period of time (which can be from 10-60 minutes or longer)has lapsed, the air flow is turned off. The top plate 100 is thenraised, and the Petri dish 52 is removed for testing. The sampler 50 canthen be sterilized, if desired, and a new Petri dish 52 introduced.

Accordingly, the air port 160 is in flow communication with thepassageway 162, which is in flow communication with the well 158. And,the well 158 is in flow communication with the elongated slots 164,which are in flow communication with air entering the holes 112 in thetop plate 100. The structure and operation of the device having thebottom plate 150 shown, is more fully described in Pub. No.2011/0167931, which is incorporated herein by reference. It should benoted, however, that any suitable bottom plate 150 can be provided otherthan the one shown, and the bottom plate 150 need not have a center well158 and air hole 162 and slots 164.

As shown in FIG. 3 , the side wall 140 defines a side wall inner surface170 and a side wall outer surface 172. The inner surface 170 defines aninner diameter of the upper plate 140. The inner surface 170 isstraight, and does not project inward, so as not to interfere with thePetri dish 52. Thus, the inner wall 170 need not be positioned furtheraway from the Petri dish 52. The straight inner wall 170 also provides astraight air conduit with uniform dimensions (i.e., width) between thePetri dish 52 and the inner wall 170, so that air can flow uniformlyaround the Petri dish 52 to the exit port 160.

The outer surface 172 of the side wall 140 is curved, and therefore theside wall 140 has a varying thickness. The side wall 140 is thicker atthe top and bottom portions, and thinner in the middle portion where itis curved inward. The outer surface 172 is curved to be ergonomic andmate with the shape of a user's gloved hand. The top of the curved outersurface 172 has a curved top lip 142 that extends around the entirecircumference of the top plate 100. The top lip 142 projects outwardfrom the middle portion of the wall 140. The top lip 142 engages theuser's fingers when the top plate 100 is being lifted, thereby making iteasier to lift and manipulate the top plate 100. The top lip 142 isrounded or beveled at the end 143 between the top surface of the flatsection 130 and the side wall 140. The rounded end 143 enhances thesafety of the top plate 100 and increases the comfort of the user, byremoving any sharp angles. An additional benefit of the curved outerwall surface 172 is that the user knows by touch that he is manipulatingthe top plate 100 (and not the bottom plate 150). Thus, for instance,the user can slide his/her fingers up from the bottom of the device 50until the fingers engage the top lip 142.

The bottom section of the curved outer wall surface 172 forms a bottomlip 144 that is relatively sharp. This provides the side wall 140 with aflat foot 146 that forms a seal and mates with the top surface of thebottom plate 150. The outer circumference of the foot 146 of the sidewall 140 where the top plate 100 meets the bottom plate 150 is sized andconfigured substantially the same as the bottom plate 150. The foot ofthe side wall 140 of the top plate 100 has an outer diameter of 4.5inches. There are twelve holes 116 positioned within about a circulararea having a 3 inch diameter, and each hole 116 has a diameter of about0.5 inches. The thickness of the top and bottom of the concaved side 140is about 0.25 inches.

The concaved outer side 140 of the top plate 100 is particularly usefulsince users are often required to wear gloves (in addition to garments,hoods, and booties) at all times while inside the clean room. Inaddition, the entire device 50 is made of metal, so that it can besterilized by heat, steam, VHP or ETO. Consequently, the top plate 100(as well as the bottom plate) is relatively heavy, which makes itdifficult to remove with a gloved hand. By providing an inwardlyconcaved outer side 140, the present invention allows the top plate 100to be easily lifted off of the bottom plate 150 without disturbing thebottom plate 150.

The curved side wall 140 also substantially reduces the weight of thetop plate 100. The weight of the top plate 100 is 1 pound, 1 ounce,which is about a 20% (18.82%) reduction in weight from the top plate 10of FIG. 1 , which weighs 1 pound, 4.2 ounces. The radius of curvature isabout 0.337 inches.

The curved outer surface 172 is preferably uniformly curved completelyaround the top plate 100. However, the outer surface 172 need not becompletely curved and only portions of the outer surface 172 can becurved. For instance, the side wall 140 can be curved at two oppositeportions of the top plate 140. Or, the side wall 140 can be curveddifferently at different portions of the side wall 140. And, the curveneed not have both a top lip 142 and a bottom lip 144. For instance,only a top lip 142 can be provided.

The foregoing description and drawings should be considered asillustrative only of the principles of the invention. The invention maybe configured in a variety of shapes and sizes and is not intended to belimited by the preferred embodiment. Numerous applications of theinvention will readily occur to those skilled in the art. Therefore, itis not desired to limit the invention to the specific examples disclosedor the exact construction and operation shown and described. Rather, allsuitable modifications and equivalents may be resorted to, fallingwithin the scope of the invention.

1.-5. (canceled)
 6. An ergonomic sampler device, comprising: a top plateincluding a top surface, a side wall with an inner surface and an outersurface, the inner surface being substantially straight and the outersurface being substantially concaved inward, a rounded lip between thetop surface and the side wall, and a plurality of through bores throughthe top surface; and a bottom plate including a top surface, a bottomsurface, a side surface, and a receiving portion at the top surface ofthe bottom plate for receiving a dish, the top surface of the bottomplate mating with the side wall of the top plate, the bottom surfacecomprising a channel terminating at a hole in the side surface, thechannel fluidly connecting the plurality of through holes of the topplate with the hole in the side surface of the bottom plate, wherein thetop plate is separable from the bottom plate by a user's fingersgripping the rounded lip and lifting the top plate.
 7. The samplerdevice of claim 6, wherein the entirety of the outer surface of the topplate is concaved.
 8. The sampler device of claim 6, wherein the sidewall has a sharp lip opposite the rounded lip.
 9. The sampler device ofclaim 8, wherein the outer surface terminates at the rounded and sharplips, respectively.
 10. The sampler device of claim 9, wherein adiameter of the rounded lip and a diameter of the sharp lip are thesame.
 11. The gas sampler device of claim 6, wherein the top plate isconfigured for use by a user wearing a glove and/or hood.
 12. The gassampler device of claim 6, wherein the top plate is metal andnon-compressible.
 13. The gas sampler device of claim 6, wherein therounded lip extends outwardly beyond the outer surface of the side wall.14. A method for providing a gas sampler device in a controlledenvironment, the gas sampler device comprising a top plate including atop surface, a side wall with an inner surface and an outer surface, theinner surface being substantially straight and the outer surface beingsubstantially concaved inward, a rounded lip between the top surface andthe side wall, and a plurality of through bores through the top surface;and a bottom plate including a top surface, a bottom surface, a sidesurface, and a receiving portion at the top surface of the bottom platefor receiving a dish, the top surface of the bottom plate mating withthe side wall of the top plate, the bottom surface comprising a channelterminating at a hole in the side surface, the channel fluidlyconnecting the plurality of through holes of the top plate with the holein the side surface of the bottom plate, the method comprising the stepof: gripping the rounded lip of the top plate with a user's fingers; andlifting the top plate from the bottom plate after the user's fingersgrip the rounded lip to separate the top plate from the top plate. 15.The method of claim 14, further comprising the step of using a glove onthe user's fingers when gripping the rounded lip.
 16. The method ofclaim 14 wherein the controlled environment is a clean room.
 17. Themethod of claim 14, wherein the entirety of the outer surface of the topplate is concaved.
 18. The method of claim 14, wherein the side wall hasa sharp lip opposite the rounded lip.
 19. The method of claim 18,wherein the outer surface terminates at the rounded and sharp lips,respectively.
 20. The method of claim 19, wherein a diameter of therounded lip and a diameter of the sharp lip are the same.